Primary essential CVG is seen in otherwise normal individuals with no other abnormalities, and thus any laboratory tests performed during clinical work up are normal, although a low free testosterone level may be present. In primary non-essential and secondary CVG, laboratory findings depend on the underlying disorder/disease and laboratory test choice should be guided by history and physical examination.

Electroencephalography (EEG) should be performed in all patients with mental deficiency and may find diffuse slowing of background activity, frequent temporal spikes, and spike-wave complexes spreading to the frontal area.

Diagnosis confirmation

The differential diagnosis for CVG includes the following:

Cutis laxa (elastolysis): Rare connective tissue disorder of elastin fibers resulting in loose, wrinkled, hanging skin folds over entire surface of body, although often most noticeable on face. In cutis laxa, skin folds are found over entire surface of the body and can be easily corrected/flattened, whereas CVG only affects the scalp and folds cannot be corrected/flattened.

Cylindroma: Benign skin appendageal tumor that may present in solitary or multiple form, most commonly on head/neck. In multiple form, tumors may enlarge and coalesce on the scalp forming a "turban tumor." This form could therefore cause folds/furrows in scalp but can be distinguished from CVG due to its nodular morphology and histologic examination.

Who is at Risk for Developing this Disease?

CVG is a rare cutaneous disorder in which multiple (typically numbering 2 to12), thickened skin folds develop in a cerebriform pattern on the scalp.

CVG has been classified into three types that help determine the cause:

Prevalence in the general population is unknown but has been estimated to be 1 in 100,000 (males) and 0.026 in 100,000 (females).

Primary CVG is 5 to 6 times more common in males than females. Longer hair in females, however, may result in undiagnosed cases.

Most cases of primary essential CVG present shortly after puberty, possibly due to rising testosterone levels. Primary non-essential is often present at birth or early childhood and is associated with obvious mental, physical, or functional abnormalities/deficiencies. Secondary CVG varies in time of presentation but may also be present at birth.

One differentiating point would be that most primary CVG patients have symmetric folds whereas secondary CVG patients would be more likely to have asymmetric folds.

What is the Cause of the Disease?

Etiology

Pathophysiology

In primary CVG, the etiology and pathophysiology are unknown; however, primary lesions may be influenced by genetic and/or endocrinologic factors such as X-linked inheritance and increased utilization of testosterone in peripheral tissues. These factors may explain the male predominance.

Secondary CVG is caused by an underlying disease that induces secondary skin changes through processes such as inflammation, lymphedema, neoplasia, or hyperplasia.

Systemic Implications and Complications

Primary essential CVG is present with no other abnormalities or known risk factors.

Appropriate work up and management is therefore dependent on the underlying disorder/disease; however, in patients with suspected primary non-essential or secondary CVG, one should typically obtain cutaneous biopsy, brain imaging (CT/MRI), EEG, and chromosomal analysis, in addition to the routine evaluation for the specific underlying condition.

Optimal Therapeutic Approach for this Disease

Assess for and then treat/manage underlying disorder/disease if present.

If CVG lesion remains after treating underlying disease, or if primary CVG, consider observation only due to the relatively benign nature of the CVG lesion.

If desired, consider a plastic surgery consultation for possible surgical excision of the CVG lesion.

Some secondary causes of CVG (e.g., cerebriform intradermal/melanocytic nevus) have the potential for malignant transformation (e.g., malignant melanoma). These lesions therefore should be surgically excised or followed regularly.

Regular hygiene is recommended for all types of CVG to avoid secondary infections in deep furrows.

Patient Management

If CVG is present at birth or if obvious underlying disorder is present, then a full evaluation (see below) for non-essential and secondary causes is indicated.

If CVG presents after puberty in otherwise normal child/adolescent, consider evaluation for secondary causes as indicated by a complete history/physical, but advanced brain imaging, EEG, etc., may not be necessary.

For suspected primary non-essential and secondary forms, a full work up consists of a complete history/physical examination, screening laboratory tests as appropriate (e.g., fasting glucose, basic chemistries, TSH, hormone levels, etc.,), brain imaging (CT/MRI), EEG, cutaneous biopsy, and chromosomal analysis, before or concurrent with expert consultation. The authors guide their work up based on the history and physical and rarely do extensive work ups unless guided by the history and physical examination.

Regular hygiene is recommended for all types of CVG to avoid secondary infections in deep furrows.

Regular follow up with the patient is recommended at least every 6 months, even in those with primary essential CVG, to document progression of the CVG lesion and to monitor care of any underlying conditions.

Treat/manage underlying disorders or diseases, but most CVG lesions do not necessarily require treatment/removal.

Patients and family should be counseled that CVG is a relatively benign lesion that typically persists unless surgically resected, and treatment/management of any underlying disorder or disease is paramount. Prognosis depends on underlying disorder/disease.

Unusual Clinical Scenarios to Consider in Patient Management

Some secondary causes of CVG (e.g., cerebriform intradermal/melanocytic nevus) have the potential for malignant transformation (e.g., malignant melanoma) and therefore should be surgically excised.

A wide variety of underlying disorders/diseases can result in a primary non-essential or secondary CVG lesion, and therefore many atypical clinical scenarios may arise depending on the underlying condition.